The present invention relates to a method of driving a thermal recording head which is effective to prevent recording density defects when employing a recorder using the thermal recording head.
A driving method for a recorder using a thermal recording head conventionally comprises heating a plurality of heating elements arranged on a substrate of the thermal recording head selectively according to picture information, thereby recording the picture information on thermally sensitive recording paper. In such a recorder, the time in which a heat pulse is impressed upon the thermal recording paper decreases as the recording speed is increased, and the quantity of heat supplied to a unit area by the heating element also tends to decrease. Therefore, the heating element is sometimes not thoroughly heated for the leading line of black information, when printing black information after white information has run successively in the subscanning direction on a high-speed recording unit, thus creating the problem that the printing density deteriorates at this portion.